Sory, for not be concreet, I reread my message, and indeed it not clear.

So here the case I have in my project, but I manage to reproduce it on Qt "mdi" example project with small modification. (Somehow I cannot upload it, so I add a link to my google drive zip archive. Do not afraid to open link).

To simulate the situation on our project, I creates 100 QMdiSubWindowses, on sturtup with next configurations:

And after showing all this MdiSubWindowses one by one after creation, application starts to steal focus from you each time, when windows appear. When I get rid of the line child->setAttribute(Qt::WA_NativeWindow); everything works ok. But I cannot do this on my real project.

For me it is not clear why this happend, because I think, that we should folow the guidlines in any configuration, for "alien" and "native" windows.

If I can do something about this, please let me know.

P.S. I tried to use Qt::WA_ShowWIthoutActivating, but it would not help, as this activation hapend in another place in code.